Hand-held controller tracked by LED mounted under a concaved dome

ABSTRACT

A hand-held controller is enables a user to manipulate objects in a VR environment with hand movement. The hand-held controller includes a handle, a ring attached to an end of the handle and one or more light emitting diodes (LEDs). The handle has appropriate shape and dimensions so that it can be grasped by the user&#39;s hand. The ring has an outer body that includes an inner surface that is formed with one or more concave dome and an outer surface facing away from the inner surface. Each of the one or more LED is mounted under a concaved dome. Light emitted from the LED spreads at the concaved dome to form uniform illuminous intensity. The light transmits out of the body through the outer surface of the outer body. The light can be captured by a camera for tracking the hand-held controller.

BACKGROUND Field of the Disclosure

The present disclosure generally relates to virtual reality (VR)controllers, and specifically to a hand-held VR controller tracked bylight emitting diodes (LEDs) mounted under concaved domes.

Description of the Related Arts

VR systems may include a controller to translate movement of the user'sbody into tangible action in a virtual world. The controller may let theuser make social gestures like point, wave, and give a thumbs-up ormanipulate objects in the virtual space, pick up toys or fire laser gunswith intuitive, natural hand movement. For example, hand-heldcontrollers are used to track a user's hand motion, position, naturalgestures, and finger movement to create a sense of hand presence formore realistic and tactile VR.

A hand-held controller is often tracked by the VR systems by using a LEDand cameras capturing light emitted by the LED. However, most illuminousintensity is distributed on the direction in which the LED emits light,the hand-held controller cannot be effectively tracked when it moves toa position where light in the emitting direction is outside the field ofview of the camera.

SUMMARY

Embodiments relate to a hand-held controller of a VR system tracked by aLED with uniform illuminator intensity over a wide range of angle. Thehand-held controller includes a handle, a ring attached to an end of thehandle, and a LED. The handle is shaped and dimension to be grasped by auser's hand. The ring has an outer body that includes an inner surfaceformed with a concaved dome and an outer surface facing away from theinner surface. The LED is mounted under the concaved dome and emit lightinto the concaved dome. The light spreads at the concaved dome. Theconcaved dome is positioned, shaped, and dimensioned to cause uniformilluminous intensity. The spread light transmits out of the ring throughthe outer surface. The light can be captured by an image device to tracka position or orientation of the hand-held controller. Because of theuniform illuminator intensity in the wide range of angles, the hand-heldcontroller can be effectively tracked even when the emitting directionof the LED is not in a field of view of the imaging device. Thehand-held controller can have more than one LEDs, each of which ismounted under a concaved dome.

In some embodiments, the hand-held controller is part of a HMD system.The HMD system may operate in a VR system environment or a mixed reality(MR) system environment. The HMD system comprises an HMD, a HMD console,and the hand-held controller. The HMD presents images (2D or 3D) to ause. A hand of the user grasps the hand-held controller and thehand-held controller is used to track motion of the hand of the user.The HMD console is coupled to the hand-held controller and the HMD andcontrols the hand-held controller and the HMD. In some embodiments, theHMD system includes another hand-held controller to track motion of theother hand of the user.

BRIEF DESCRIPTION OF THE DRAWINGS

The teachings of the embodiments can be readily understood byconsidering the following detailed description in conjunction with theaccompanying drawings.

FIG. 1 is an example schematic perspective view of a hand-heldcontroller, in accordance with an embodiment.

FIG. 2 is an example schematic perspective view of a ring of thehand-held controller, in accordance with an embodiment.

FIG. 3 is a cross-sectional view of the ring of the hand-heldcontroller, in accordance with an embodiment.

FIG. 4 is a diagram showing position, shape, and dimensions of aconcaved dome under which a LED is mounted, in accordance with anembodiment.

FIG. 5A is a diagram illustrating distribution of illuminous intensityof a LED that is not mounted under a concaved dome, in accordance withan embodiment.

FIG. 5B is a diagram illustrating distribution of illuminous intensityof a LED that is mounted under a concaved dome, in accordance with anembodiment.

FIG. 6 is a block diagram of a HMD system in which the hand-heldcontroller operates, in accordance with an embodiment.

The figures depict various embodiments for purposes of illustrationonly.

DETAILED DESCRIPTION

In the following description of embodiments, numerous specific detailsare set forth in order to provide more thorough understanding. However,note that the embodiments may be practiced without one or more of thesespecific details. In other instances, well-known features have not beendescribed in detail to avoid unnecessarily complicating the description.

Embodiments are described herein with reference to the figures wherelike reference numbers indicate identical or functionally similarelements. Also in the figures, the left most digits of each referencenumber corresponds to the figure in which the reference number is firstused.

Embodiments relate to a hand-held VR controller to track a user's handmotion and position. The hand-held controller includes a handleextending in a longitudinal direction. A body is attached to an end ofthe handle and has a curved outer surface and a curved inner surface.LEDs are mounted on the curved outer surface and configured to emitlight to be captured by an imaging device for tracking a position ororientation of the hand-held controller.

FIG. 1 is an example schematic perspective view of a hand-heldcontroller 100, in accordance with an embodiment. The hand-heldcontroller 100 may be included in a VR system as a stand-alonecontroller or as part of a pair of tracked controllers that give a user“hand presence”—the feeling that the user's virtual hands are actuallyhis own. The hand-held controller 100 may enable the user to manipulateobjects in a virtual space with precision and intuitive, natural handmovement. The hand-held controller 100 includes a handle 104, a ring112, and a trigger button 136. In other embodiments, the hand-heldcontroller 100 can include different, additional, or fewer components.

The handle 104 extends in a longitudinal direction 108. In oneembodiment, the handle 104 may be made of an engineering plastic, suchas injection-molded polycarbonate (PC)/acrylonitrile butadiene styrene(ABS) or polyamide (nylon). In other embodiments, the handle 104 may bemade of wood or metal. The handle 104 may be resistant to impact andabrasion. The material of the handle 104 may exhibit heat resistance,mechanical strength, or rigidity.

The handle 104 is shaped and dimensioned to be grasped by a user's handfor tracking natural gestures and finger movements to create morerealistic and tactile VR. For example, the handle may have a cylindricalshape. The handle 104 of the hand-held controller 100 may bend or curveto balance the weight of the controller 100, such that it restsnaturally in the top of the palm of the user or the crook of the user'sfingers. The user may therefore comfortably hold the hand-heldcontroller 100 without dropping it. Even if the user tries to open hishand completely when holding the hand-held controller 100 normally, theuser's fingers may catch on the ring 112 and support the hand-heldcontroller 100's weight.

The ring 112 is attached to an end of the handle 104 and has an annularsurface 120. The ring may be made of engineering plastic. In oneembodiment, the ring is made of infrared-transparent polycarbonate. Thering 112 may surround a thumb of the user when the handle 104 is graspedby the user's hand. The ring 112 has an outer body 116. As illustratedin FIG. 1, the outer body 116 is curved. In other embodiments, the outerbody 116 may have other shapes. The curved outer body 116 includes aninner surface 330 and an outer surface 340 facing away from the innersurface 330 (shown in FIG. 3). The inner surface 330 is formed with aplurality of concaved domes 310 (shown in FIG. 3)

The LEDs 128 are mounted under the concaved domes 310, i.e., under theouter body 116. For purpose of illustration, the LEDs 128 are shown inFIG. 1 but they may be occluded under the outer body 116. In embodimentswhere the outer body 116 is transparent or translucent, the LEDs 128 canbe at least partially visible. In some embodiment, each of the LEDs 128is mounted under a concaved dome 310. A LED 128 faces the concaved dome310 and emits light to the concaved dome 310. The concave dome 310 ispositioned, shaped, and dimensioned to spread the emitted light foruniform illumination intensity. The light 132 transmits out of the outerbody 116 through the outer surface 340. A VR system may include a camerato track a position or orientation of the hand-held controller 100 bycapturing the light 132. For example, a camera may be mounted on acomputer monitor covering a field of view including the hand-heldcontroller 100.

The trigger button 136 is located on a bottom surface 140 of the handle104. The trigger button 136 may be pressed by an index or middle fingerof the user's hand. The trigger button 136 may provide a signal forgrasping, lifting, etc., of virtual objects in a VR space. The triggerbutton 136 may have a symmetrical shape, such as rectangular, ellipticalor circular. The trigger button 136 may be made of rubber or plastic.

FIG. 2 is an example schematic perspective view of a ring 112 of thehand-held controller 100, in accordance with an embodiment. The ring hasthe curved outer surface 116. A group of LEDs 128 are located under theouter body 116. FIG. 2 shows eight LEDs 128 on the ring 112. Differentembodiments may have a different number of LEDs 128. The LEDs 128 canemit light in the visible band (i.e., ˜380 nm to 750 nm), in theinfrared (IR) band (i.e., ˜750 nm to 1 mm), in the ultraviolet band(i.e., 10 nm to 380 nm), some other portion of the electromagneticspectrum, or some combination thereof.

FIG. 3 is a cross-sectional view 300 of the ring 112 of the hand-heldcontroller 100, in accordance with an embodiment. The cross-sectionalview 300 is taken along a cross-section to illustrate only a single LED128. As shown in FIG. 3, the LED 128 is attached on a mount 320 under aconcaved dome 310. A portion of the LED 128, including a top surface ofthe LED 128 is enclosed within the concaved dome 310. In someembodiments, 0.2 mm of the LED 128's top surface is recessed into theconcaved dome.

The concaved dome 310 may be formed by carving out the inner surface 340of the outer body 116. In the embodiment of FIG. 3, the inner surface340 and the outer surface 350 of the outer body 116 are curved. In analternative embodiment, either the inner surface 340 or the outersurface 350 can be flat. The LED 128 faces the concaved dome to emitlight into the concaved dome 310. The light emitted from the LED 128reaches the concaved dome 310 and is spread at the concaved dome 310into multiple directions. The concave dome 310 is positioned, shaped,and dimensioned to achieve generally uniform illumination intensitybetween approximately −90 degrees from the light emitting direction andapproximately 90 degrees from the light emitting direction. More detailsregarding position, shape and dimension of the concaved dome 310 areprovided in conjunction with FIG. 4.

The light with uniform illuminous intensity transmits out of the outersurface 340 and can be captured by an imaging device within its field ofview. The imaging device generates tracking information, e.g., images ofthe hand-held controller 100, based on the captured light. The VR systemthen uses the tracking information to track a position or orientation ofthe hand-held controller 100. Because the light has uniform illuminousintensity between approximately −90 degrees from the light emittingdirection and approximately 90 degrees from the light emittingdirection, the hand-held controller 100 can be effectively tracked bythe imaging device even if it moves to a position where the top of theLED faces the imaging device in a slanted angle or even when the top ofthe LED faces in a direction perpendicular to the direction towards theimaging device.

FIG. 4 is a diagram showing position, shape, and dimensions of aconcaved dome 310 under which a LED 128 is mounted, in accordance withan embodiment. The LED 128 is attached on a mount 320. FIG. 4 shows theright half of the concaved dome 310, the LED 128, and the mount 320. Inthe embodiment of FIG. 4, the left half of the concaved dome 310, theLED 128, and the mount 320 mirrors their right half, i.e., the concaveddome 310, the LED 128, and the mount 320 are symmetric. In otherembodiments, the left and the right sides of the concaved dome 310, theLED 128, and the mount 320 can by asymmetric.

As shown in FIG. 4, the center of the top surface lines up with thecenter of the concaved dome 310. Also, a top surface of the LED 128 isrecessed into the concaved dome 310 by T1. In some embodiments, T1 fallsinto a range from 0.1 to 0.3 mm. For example, T1 is 0.2 mm.

In the embodiment of FIG. 4, the top surface of the LED 128 is arectangular. The rectangular has a length of 2.3 mm. In otherembodiments, the top surface of the LED 128 can have different shapeswith different dimensions. In some embodiments, a ratio of a length ofthe top surface of the LED 128 to a radius R1 of the concaved dome 310is approximately 1.3. An opening angle A1 of the concaved dome 310 is 45to 55 degrees. In one embodiment, the concaved dome 310 has a depth D1of 0.8 mm, a radius R1 of 1.75 mm, and an opening angle A1 of 50degrees.

FIG. 5A is a diagram 500 illustrating distribution of illuminousintensity of a LED that is not mounted under a concaved dome, inaccordance with an embodiment. The LED has an emitting direction that isnormal to a top surface of the LED. The diagram 500 shows the illuminousintensity of the LED as a function of angle. In some embodiments, theangle is beam angle, i.e., an angle between a light beam from theemitting direction of the LED. The emitting direction of the LED has abeam angle of 0 degree.

The diagram 500 shows the illuminous intensity of the LED from −90 to 90degrees. As shown in FIG. 5A, the light beam at 0 degree (i.e., theemitting direction) has the highest illumination intensity, but theintensity drops significantly as the angle increases. Thus, light beamsin directions other than the emitting direction has significantly lowilluminous intensity. Accordingly, an imaging device can barely capturelight emitted from the LED when the LED is in a position where itsemitting direction is not in the field of view of the imaging device.The imaging device cannot generate effective tracking information.

FIG. 5B is a diagram 550 illustrating distribution of illuminousintensity of a LED that is mounted under a concaved dome, in accordancewith an embodiment. Compared with the diagram 500, the diagram 550 showsa relatively uniform distribution of illuminous intensity from −90degrees to 90 degrees, indicating that light beams in directions otherthan the emitting direction has substantially similar illuminousintensity as the light beam in the emitting direction. Thus, even whenthe LED is in a position where its emitting direction is not in thefield of view of the imaging device, the imaging device can stillcapture light to generate effective tracking information.

FIG. 6 is a block diagram of a HMD system 600 in which the hand-heldcontroller 100 operates, in accordance with an embodiment. The HMDsystem 600 may operate in a VR system environment or an MR systemenvironment. The HMD system 600 shown by FIG. 6 comprises a HMD console610 coupled to a HMD 620 and a hand-held controller 630. While FIG. 6shows an example system 600 including one HMD 620 and one hand-heldcontroller 630, in other embodiments any number of these components maybe included in the system 600. For example, there may be multiple HMDs620, each having an associated hand-held controller 630 andcommunicating with the HMD console 610. In alternative configurations,different and/or additional components may be included in the HMD system600. Similarly, functionality of one or more of the components can bedistributed among the components in a different manner than is describedhere. For example, some or all of the functionality of the HMD console610 may be contained within the HMD 620.

The HMD 620 is a head-mounted display that presents content to a usercomprising virtual and/or augmented views of a physical, real-worldenvironment with computer-generated elements (e.g., 2D or 3D images, 2Dor 3D video, sound, etc.). Examples of media presented by the HMD 620include one or more images, video, audio, or some combination thereof.In some embodiments, audio is presented via an external device (e.g.,speakers and/or headphones) that receives audio information from the HMD620, the HMD console 610, or both, and presents audio data based on theaudio information.

The HMD 620 includes an electronic display 622, an optics block 624, aninertial measurement unit (IMU) 627, one or more position sensors 626,and a reference point 628. Some embodiments of the HMD 620 havedifferent components than those described here.

The IMU 627 is an electronic device that generates fast calibration databased on measurement signals received from one or more of the positionsensors 626. A position sensor 626 generates one or more measurementsignals in response to motion of the HMD 620. Examples of positionsensors 626 include: one or more accelerometers, one or more gyroscopes,one or more magnetometers, another suitable type of sensor that detectsmotion, a type of sensor used for error correction of the IMU 627, orsome combination thereof. The position sensors 626 may be locatedexternal to the IMU 627, internal to the IMU 627, or some combinationthereof.

Based on the one or more measurement signals from one or more positionsensors 626, the IMU 627 generates fast calibration data indicating anestimated position of the HMD 620 relative to an initial position of theHMD 620. For example, the position sensors 626 include multipleaccelerometers to measure translational motion (forward/back, up/down,left/right) and multiple gyroscopes to measure rotational motion (e.g.,pitch, yaw, or roll). In some embodiments, the IMU 627 rapidly samplesthe measurement signals and calculates the estimated position of the HMD620 from the sampled data. For example, the IMU 627 integrates themeasurement signals received from the accelerometers over time toestimate a velocity vector and integrates the velocity vector over timeto determine an estimated position of a reference point on the HMD 620.The reference point 628 is a point that may be used to describe theposition of the HMD 620. While the reference point may generally bedefined as a point in space; however, in practice the reference point isdefined as a point within the HMD 620 (e.g., a center of the IMU 627).

In some embodiments, the IMU 627 receives one or more calibrationparameters, e.g., from the HMD console 610. The one or more calibrationparameters are used to maintain tracking of the HMD 620. Based on areceived calibration parameter, the IMU 627 may adjust one or more IMUparameters (e.g., sample rate). In some embodiments, certain calibrationparameters cause the IMU 627 to update an initial position of thereference point 628 so it corresponds to a next calibrated position ofthe reference point 628. Updating the initial position of the referencepoint 628 as the next calibrated position of the reference point 628helps reduce accumulated error associated with the determined estimatedposition. The accumulated error, also referred to as drift error, causesthe estimated position of the reference point 628 to “drift” away fromthe actual position of the reference point 628 over time.

The hand-held controller 630 is a device that allows a user to sendaction requests to the HMD console 610. An action request is a requestto perform a particular action. For example, an action request may be tostart or end an application or to perform a particular action within theapplication. The hand-held controller 630 may include one or more inputdevices. Example input devices include: a keyboard, a mouse, a gamecontroller, or any other suitable device for receiving action requestsand communicating the received action requests to the HMD console 610.

An action request received by the hand-held controller 630 iscommunicated to the HMD console 610, which performs an actioncorresponding to the action request. In some embodiments, the hand-heldcontroller 630 may provide haptic feedback to the user in accordancewith instructions received from the HMD console 610. For example, hapticfeedback is provided when an action request is received, or the HMDconsole 610 communicates instructions to the hand-held controller 630causing the hand-held controller 630 to generate haptic feedback whenthe HMD console 610 performs an action. An embodiment of the hand-heldcontroller 630 is the hand-held controller 100 described in conjunctionwith FIG. 1.

The HMD console 610 provides media to the HMD 620 for presentation tothe user in accordance with information received from the HMD 620 and/orthe Hand-held controller 100. In the example shown in FIG. 6, the HMDconsole 610 includes an application store 612, a tracking module 614,and a HMD engine 616. Some embodiments of the HMD console 610 havedifferent modules than those described in conjunction with FIG. 6.Similarly, the functions further described below may be distributedamong components of the HMD console 610 in a different manner than isdescribed here.

The application store 612 stores one or more applications for executionby the HMD console 610. An application is a group of instructions, thatwhen executed by a processor, generates content for presentation to theuser. Content generated by an application may be in response to inputsreceived from the user via movement of the HMD 620 or the Hand-heldcontroller 100. Examples of applications include: gaming applications,conferencing applications, video playback application, or other suitableapplications.

The tracking module 614 calibrates the HMD system 600 using one or morecalibration parameters and may adjust one or more calibration parametersto reduce error in determination of the position of the HMD 620.Moreover, calibration performed by the tracking module 614 also accountsfor information received from the IMU 627. Additionally, if tracking ofthe HMD 620 is lost, the tracking module 614 re-calibrates some or allof the HMD system 600.

The tracking module 614 tracks movements of the HMD 620. The trackingmodule 614 determines positions of a reference point of the HMD 620using position information from fast calibration information.Additionally, in some embodiments, the tracking module 614 may useportions of the fast calibration information to predict a futurelocation of the HMD 620. Alternatively, the tracking module 614 may usedepth information generated by the DMA 300 to track movements of the HMD620. For example, the DMA 300 generates depth information of an objectthat is still as to the local area surrounding the HMD 620. Using thedepth information, the tracing module 614 can determine movements of theobject relative to the HMD 620, which is opposite to movements of theHMD 620 in the local area. The tracking module 614 provides theestimated or predicted future position of the HMD 620 to the HMD engine616.

The HMD engine 616 executes applications within the system environment100 and receives depth information, position information, accelerationinformation, velocity information, predicted future positions, or somecombination thereof of the HMD 620 from the tracking module 614. Basedon the received information, the HMD engine 616 determines content toprovide to the HMD 620 for presentation to the user. For example, if thereceived depth information indicates that an object has moved furtherfrom the HMD 620, the HMD engine 616 generates content for the HMD 620that mirrors the object's movement in an augmented reality environment.Additionally, the HMD engine 616 performs an action within anapplication executing on the HMD console 610 in response to an actionrequest received from the Hand-held controller 100 and provides feedbackto the user that the action was performed. The provided feedback may bevisual or audible feedback via the HMD 620 or haptic feedback via theHand-held controller 100.

The language used in the specification has been principally selected forreadability and instructional purposes, and it may not have beenselected to delineate or circumscribe the inventive subject matter. Itis therefore intended that the scope be limited not by this detaileddescription, but rather by any claims that issue on an application basedhereon. Accordingly, the disclosure of the embodiments is intended to beillustrative, but not limiting, of the scope, which is set forth in thefollowing claims.

What is claimed is:
 1. A handheld controller, comprising: a handleshaped and dimensioned to be grasped by a user's hand; a body attachedto an end of the handle, the body having: an inner surface formed with aplurality of concaved domes, and an outer surface facing away from theinner surface; and a plurality of light emitting diodes (LEDs) emittinglight, each of the LEDs mounted under each of the plurality of concaveddomes and facing the concaved dome to emit light into the concaved dome,wherein the light emitted by the LEDs is spread at the concaved domesand transmitted out of the body through the outer surface for capturingby an imaging device to track a position or orientation of the handheldcontroller.
 2. The device of claim 1, wherein a top surface of each ofthe LEDs is enclosed by the corresponding concaved dome.
 3. The deviceof claim 1, wherein an opening angle of each of the plurality ofconcaved domes is 45 to 55 degrees.
 4. The device of claim 1, wherein aratio of a length of each of the LEDs to a radius of the correspondingconcaved dome is approximately 1.3.
 5. The device of claim 1, wherein0.2 mm of each of the LEDs is recessed into the corresponding concaveddome.
 6. The device of claim 1, wherein the outer surface and the innersurface of the body are curved.
 7. A method of emitting light to track ahandheld controller, comprising: emitting light from each of a pluralityof light emitting diodes (LEDs) to each of a plurality of concaved domesin an inner surface of the handheld controller, at least a portion ofeach of the LEDs enclosed within the corresponding concaved dome;spreading the emitted light at the plurality of concaved domes byrefraction; and transmitting the refracted light out of the body throughan outer surface of the handheld controller for capturing by an imagingdevice to track a position or orientation of the handheld controller. 8.The method of claim 7, wherein a top surface of each of the LEDs isenclosed by the corresponding concaved dome.
 9. The method of claim 7,wherein an opening angle of each of the plurality of concaved domes is45 to 55 degrees.
 10. The method of claim 7, wherein a ratio of a lengthof each of the LEDs to a radius of the corresponding concaved dome isapproximately 1.3.
 11. The method of claim 7, wherein 0.2 mm of each ofthe LEDs is recessed into the corresponding concaved dome.
 12. Themethod of claim 7, wherein the outer surface and the inner surface ofthe body are curved.